Driving mechanism



Feb. 10, 1942. s. E. sCHRoEbER 2,272,853

DRIVING MECHANISM Filed Dec. 51, 1940 T--umlll figa/'figa' Patented Feb. 10, 1942 2,272,853 DRIVING MECHANISM Simon E. Schroeder, Ripon, Wis., assignor to Barlow & Seelig Manufacturing Company, Ripon, Wis., a corporation of Delaware Application December 31, 1940, Serial No. 372,548

(Cl. i4-209) l Claim.

The invention relates to a drive mechanism of a type especially well adapted for use in establishing a driving connection between a water pump in a washing or laundry machine or the like and the source of power for operating such a machine.

It is an object of the invention to provide a new and improved drive mechanism of this general type characterized in one of more of the following respects: (a) ease of engagement and disengagement, (b) self-adjustment to compensate for wear, greater manufacturing tolerances and installation inaccuracies, (c) extreme simplicity combined with durable, positive and efcient power transmission.

More specically stated, it is an object of the invention to provide, in a device of the above mentioned general type, an idler wheel constituting an intermediate driving connection between a pair of driving and driven members and supported for swinging movement about the axis of one of said members, preferably the driven member, into and out of frictional driving engagement with said members and being provided with a looseness or lost motion permitting self-centering of the idler upon engagement to effect a iirm frictional connection between the driving and driven members.

Further objects and advantages of the invention will become apparent as the following description proceeds taken in connection with the accompanying drawing, in which:

Figure 1 is a fragmentary plan view of the lower portion of a washing machine below the tub and shows a pump drive mechanism embodying the features of the present invention.

Fig. 2 is a sectional view taken on the line 2-2 of Fig. l through the washing machine frame and showing the drive mechanism in elevation.

Fig. 3 is a detail sectional view of the drive taken on line 3-3 of Fig. 1.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawing and will herein describe in detail the preferred embodiment, but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claim.

The drive mechanism embodying the subject matter of the present invention has been illustrated in connection with a pump for a washing gedness of the mechanism, as well as its ease and efciency of operation, make it particularly adaptable for such use. It is to be understood, however, that the drive mechanism may be advantageously used in other environments.

Referring more specically to the drawing, a conventional type of rotary water pump I0, is mounted by means of a pair of brackets Il and l2, bolted, as at I3, on the under side of a washing machine frame Ill. The pumping mechanism constitutes no part of the present invention and may be of any suitable construction. In the present instance it comprises generally an open face pump housing l5 having intake and outlet ports I 6, Il respectively, and sealed by closure plate i8. Within the housing is an impeller (not shown) l which is rotatably driven by a pump shaft 2l extending in an axial direction through a boss 22 on the housing. A pulley 25 is suitably fixed on the outer end of the shaft 2 I.

The present drive mechanism for the pump unit is of the friction type in which a rotary idler member 34 is mounted for movement into and out of engagement with the driven pulley 25 on the pump shaft and a rotary driving element, such as a belted wheel 3 constituting, in the instant embodiment, a part of the driving mechanism for the washing machine. To the end that a convenient, compact and easily mountable unit may be provided, the idler wheel 34 is mounted on the pump by a bracket 3i for swinging movement about the axis of the pump drive shaft to frictionally engage the driving and driven wheels. The unitary structure, thus provided, may be conveniently mounted on the washing machine frame so as to dispose the driven wheel 25 in substantially coplanar spaced relation to the belted driving wheel 30. The idler wheel, which has a greater diameter dimension than the space between the driving and driven wheels, is arranged to be swung into and out of driving engagement with both wheels. The idler wheel 34 is rotatably supported on a stud 35 rigidly secured on the bracket and such means as a retaining washer 36 and a cotter pin 31 maintain the assembly. The idler wheel itself may be formed of a suitably molded plastic material having a peripheral contact surface 38 of soft rubber thereon to produce an eiiicient frictional driving connection with the driving and driven wheels.

To dispose the idler in the plane of the driving and driven wheels, its supporting bracket 3i is oiset, as at 33, intermediate the stud 35 and its pivotal connection 32 with the boss 22 on machine since the simplicity and structural rugthe pump housing. The pivotal connection of the bracket with its supporting means is provided with a looseness or lost motion to produce a firm frictional contact of the idler wheel with the driving and driven wheels. This st motion connection permits movement of the idler radially inwardly or outwardly relative to the axis of the driven pulley 25 and upon engagement permits the idler to center itself between the contacting surfaces. In the present instance, the lost motion is obtained by forming a collar 39 (Fig. 3) on .the bracket 3| with an inner diameter larger than the outside diameter of the reduced portion 40 of the boss 22 about which the collar bears. The bracket may be retained in place on the boss by a washer 4l held by a hollow flanged nut 42 internally screw threaded in the boss and carrying bushings 43 which serve as bearings for the pump shaft.

Means are provided for yieldably biasing the idler wheel into driving engagement with the driving and driven wheels 3D and 25. Thus, a coiled tension spring 44 has one end secured on the stationary bracket Il, as at 45, while its other end is secured to the swinging bracket 3|, as at 4%. It will be seen that the force of the spring is exerted to draw the idler into engaged position and also to draw the bracket toward the pump shaft thereby to take up the looseness of the lost motion connection between the swinging bracket and its supporting journal.

Manipulable means for drawing the idler from its engaged position to a disengaged position in the present instance comprises a link 41 rigidly secured, as by machine screws 48, to the swinging bracket 3! and engaged at its opposite end by a lever 49 which may project outwardly from the washing machine frame for manual operation.

It will be observed that retraction of the lever 49 will draw the idler to a disengaged position against the force of the spring 44 and, upon release of the idler supporting means to the force of the spring, the idler will swing from its retracted position about the axis of the pump shaft for frctonal engagement with the driving and driven wheels. In this connection it is to be noted that the direction of rotation of the driver, as indicated by the arrows in Fig. 1, is such that the forces due to the resistance torque between the idler and the driving and driven wheels, respectively, act in the direction of the force exerted by the spring whereby to assist in maintaining a firm frictional contact and thus an eicient transmission of power. Furthermore, the provision of a looseness or lost motion between the idler wheel and the driven Wheel about which it oscillates obviates the necessity for close manufacturing tolerances and extremely accurate installation in that the idler wheel is, in effect, self-centering upon engagement. In addition, wearing of the bearings of the pump shaft or idler or of the contact surfaces of the rotary elements will not reduce the efciency of the rictional driving connection because the lost motion permits the idler to seek automatically a rm frictional contact with the driving and driven wheels regardless of small variations in the spacing ofthe engaging elements.

I claim as my invention:

A mechanism of the character described comprising, in combination, a driving pulley, a shaft adapted to be driven, means including a hub for rotatably supporting said shaft, a pulley on said shaft disposed in spaced relation to said driving pulley, a bracket, an idler wheel carried by said bracket, a bearing formed in said bracket and journaled on said hub for swinging movement of said bracket to engage said idler wheel with said driving and driven pulleys, spring means for yieldably urging said idler into engagement with said pulleys, means for manipulating said bracket to a disengaged position against the force of said spring means, said bearing having a greater diameter than the hub on which it is journaled permitting centering of said idler wheel between said pulleys under the influence of said spring means upon engagement.

SIMON E, SCHROEDER. 

